Aroma diffuser



FIG. 1 is a front elevational view of an aroma diffuser showing my new design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is a front and left side perspective view thereof; and,

FIG. 8 is a rear and right side perspective view thereof.

The broken lines in the drawings illustrate portions of the aroma diffuser which form no part of the claimed design. 

CLAIM The ornamental design for an aroma diffuser, as shown and described. 